The following relates generally to determining a heart rate, and more specifically to automatic estimation of pulse deficit.
In a healthcare facility such as a hospital, physiological parameters of the patient (e.g., heart rate, respiratory rate, blood pressure) may be monitored by one or more medical devices. The medical devices may be battery powered and may wirelessly transmit measured patient data over a wireless network within the hospital, thereby allowing the patient to move freely through the hospital while being monitored. Clinicians may remotely monitor the patient by accessing the patient data at a central nurse station or on any web enabled device connected to the network (e.g., smartphone or tablet).
Various physiological parameters may be monitored. A typical monitored physiological parameter is a patient's heart rate. However, monitoring of a heart rate alone may not be sufficient to detect a clinical condition known as pulseless electrical activity (PEA). PEA is a clinical condition of cardiac arrest characterized by cardiac electrical activity that shows an observable heart rhythm that would normally be accompanied by a mechanical pulse of the heart, but where no pulse is actually generated. Under normal circumstances, electrical activation of muscle cells precedes mechanical contractions of the heart. During PEA, however, electrical activity is observed, but the heart either does not contract or contractions are insufficient to generate a pulse and supply blood to a person's organs. In other words, in a person susceptible to PEA, cardiac mechanical activity may not necessarily follow cardiac electrical activity. PEA may lead to a loss of cardiac output. As a result, blood supply to various organs, including to the brain, may be interrupted. Consequently, a person may lose consciousness and/or stop breathing, which may sometimes be the first observable signs that a person is suffering from PEA.
Relying on a person to lose consciousness or stop breathing is not an ideal method to discover that a person is suffering from PEA. Nevertheless, constant observation by a medical professional or caretaker may not be feasible. Therefore, improvements in monitoring and detecting PEA are desired.